Designing for experience requires designers to pay attention to reflection on design impact. However, industrial design students are observed to have difficulty in demonstrating the impact of their design concepts due to insufficient thinking and reflection on design impact. There is a lack in the literature on both reflections on design impact and the tool support. The existing tools for general reflection purpose seem not to work well for this specific purpose. In response to the calls for designing for reflection, this paper presents two exploratory studies and the design requirements of tools for reflection on design impact. The purpose aims to facilitate design students for their reflection on design impact through developing appropriate tools. The design requirements could be generally used as guidelines or reference for future work of developing tools for reflection on design impact.